锌铝合金中稀土及杂质的晶界行为  

Grain Boundary Behavior of Rare Earths and Impurities in ZA Alloy

作　　者：张国英[1] 刘春明[1] 魏丹[2] 王丹[2] 

机构地区：[1]东北大学材料与冶金学院,辽宁沈阳110004 [2]沈阳师范大学物理科学与技术学院,辽宁沈阳110034

出　　处：《东北大学学报（自然科学版）》2007年第2期209-212,共4页Journal of Northeastern University(Natural Science)

基　　金：国家自然科学基金资助项目(5067106950571071);辽宁省教育厅科学研究计划项目(05L297)

摘　　要：用分子动力学方法获得了液态ZA27合金的原子集团,构造出ZA27合金α相与液相界面原子模型及α相大角度晶界模型.采用递归法计算了稀土及杂质元素在晶粒内、固液相界面及α相晶界处的环境敏感镶嵌能,分析了这些元素对晶界处铝、锌之间电子转移量的影响.从理论角度说明稀土、杂质元素在结晶时富集于固液相界前沿液体中,合金凝固后偏聚于晶界,并在晶界产生复杂的交互作用,进而影响合金的使用性能.Experimental results showed that rare earth （RE） and impurities are liable to segregate on grain boundaries （GB） and affect greatly the properties of ZA alloy. To understand theoretically the relevant process, an atomic cluster of liquid ZA27 was formed by way of molecular dynamics, the atomic structure models of a phase/liquid interface and of a phase big angle GB were established. Recursive method was used to calculate the environment-sensitive embedding energy （EESE） of RE/impurities in grains and on solid/liquid interface and a phase GB, thus discussing the influence of REs or impurities on the electron transfer between AI and Zn. The calculation results expounded theoretically that REs and impurities are both enriched in the liquid in front of the solid/liquid interface during crystallization. After solidification, they segregate on the GB and interact complexly with each other to affect the properties of Zn-Al alloy.

关 键 词：稀土 杂质 晶界 递归方法 电子结构 

分 类 号：TG111.1[金属学及工艺—物理冶金]